Automatic machine tool



Dec. 29, 1931. A M ;QHNSON 1,838,945

AUTOMATIC MACHINE TOOL Filed Sept. 16. 1927 4 Sheets-Sheet l Dec. 29,1931.

A. M. JOHNSON AUTOMATIC MACHINE TOOL 4 Sheets-Sheet 2 l Filed sept. 16.1927 Dec. 29, 1931. A. M, JQHNSON 1,838,945

AUTOMATI C MACHINE TOOL Filed sept. 1e, 1927 4 sheets-sheet s Dec. 29,1931. A. M, JOHNSQN 1,838,945

AUTOMATIC MACHINE TOOL Filed Sept` 16. 1927 4 Sheets-Sheet 4 PatentedDee.' 29,1931

UNITED STATES PATENT "o1-FICE .ALBERT 1n. JOHNSON, oF 116012111031),-ILLINoTs, AssIGNon. 'ro BARNES DRILL coMPaNY,

or ROCKFORRTLLINOIS, A conronATIoNgoF ILLINoTsan'ronta'rrc MACHINE ToonApplication led September 16, 1927. Serial No. 219,833.

The invention has general reference vto machine tools and relates morepartlcularly to machine tools .of the automatic type em-l ployed fordrillin boring, facing and similar operations. uch machines commonly`employ one or more tool-carrying spindles mounted for lon itudinal androtational movements, and t e present invention has for its eneral aimthe rovision of improved means or presentin tK e cutting tool to dif`ferent pieces of wor in rapid'succession.

The primary-object of the invention is to provide an automaticallycontrolled s indlefeeding cam means of an improve character operable to|effect periodic vreciprocations of the tool spindle in rapidsuccession,t in each of which' thespindle in its movement toward thework rst travels at high speed to effect a rapid approach,`then at aslow or working speed during the cutting portion` of the stroke, andfinally returns to its initial positon substantially instantaneously.

Anotherobject is to provide, in combination with an automaticallyreciprocated spindle.,I a work-table-indexing mechanism automaticallycontrolled in accordance with the movements of the spindle so as topresent pieces of work to the cutting tool in proper timed relation. v Y

A further object is to provide, in combination with an automaticallyreciprocated spindle in which. a rapid approach movement is imparted tothe cutting tool, an automatic. control mechanism for the work tablewhereby the latter is indexed in advance of' the rapld approach movementof the cutting tool, so that the tool may be fed at high speed intopieces of work of substantialV depth, thus avoiding the delay incident'to moving the tool into the work at the slow-or feeding' speed as isrequired where the indexing operatiron occurs simultaneously with therapid approach lmovement of the tool.

general object is to provide a machine of the character indicated whichis relatively simple in construction and positive and that variouschanges in the construction and arrangement set forth may be 'made bythose skilled in the art without departing from the spirit and scope 0f'the invention as expressed in the appended claim.

Figure 1 of the drawings is a fragmentary elevational view of one sideof a machine tool embodying my invention.

Fig. 2 is asimilar view looking from the opposite side of the machine.

Fig. 3 is a horizontal `fragmentary planv view of the control mechanismfor the indexing work table. "i

Fig. 4= is a fragmentary vertical sectional' i view'. takenapproximately in the plane of line4-4ofFi .3. A

Fig. 5 is a ragmentary longitudinal section taken approximately in theplane of line -5-5 of Fig. 3 and showing details of construction. y

Fig. 6 is a fragmentary plan view of the work table and its supportingslide.

Fig. 7 is aV` fragmentary vertical sectional viewtaken approximately inthe plane of line 7-7 of Fig. 2, but on a larger scale..

Fig. 8 is a transverse sectional view taken` pprozximately in the planeof line 8-8 of Referring now to the drawings, I have -shownand willhereinafter describe my invention as applied to a machine tool of thetype in which a single tool spindle is mounted for vertical recirocation relative to a rotary work table, for t e erformance in rapidsuccessiorLof drilling, oring, facing or similar operations upon piecesof .work presented in timed relation to'the cutting tool. The machineherein shown comprises a frame mounted upon an upright standard 10 andhaving an inclined lupper orti'on 11 constituting a housing for a speechange mechanism generally designated by the numeral 12. At the lowerrear end of the inclined housing 11 is a box 13 enclosing the drivemechanism 'for themachine, with which is associated an automatic controlmechanism 14 operatively connected on the' one hand with means for ereciprocating the sfpindle and on the otherv a tended forwardly toprovide an arm 15 carryend of the spindle passes through and isjournaled in a forward extension 18 of thev inclined housing 11, saidforward extension 18 serving to enclose a bevel gear 19 with which apinion 2O at the terminal end of the speed change mechanism is inconstant mesh. The lower end of the spindle may carry a suitable chuck21 for a cutting tool 22; and the upper end of the spindle is in thepresent instance provided with a coiled spring 23 acting between thebevel ear 19 and a collar` 24 for the purpose of e ecting the rapidreturn stroke of the spindle after its downward movement by the feedmechanism.

The feed mechanism is preferably a cam means driven from the speedchange mechanism through the medium of a spiral gearing 25 whichdelivers power to'fsuitable speed reduction gearing in a feed box 26.The latter is pivotally supported at one side of the inclined frameportion or housing 11 and has depending therefrom a worm 27 movable intoand out of mesh with a worm wheel 28 on a transverse shaft 29 journaledin the arm 15 of the frame. Rigid with the shaft 29 on the opposite sideof the arm 15 is a pinion 30 meshing with an internal gear 31 formed ina drum 32. The drum is journaled on a sleeve 33 fixed in the arm 15 andforming a bearing for a cross feed shaft 34 parallel with shaft 29.

Rigid with the drum is a peripheral cam 35, the cam being preferablyremovably secured to the drum as by means of screws 35a engaging in aperipheral flange on the drum. Coacting'with this cam 35 is a roller 36carried by a gear element 37 in the form of a segment mounted on a stud'38 carried by the standard 10. The segment 37 in turn meshes withapinion 39 which in the present embodiment has a normal drivingconnection with the cross feed shaft 34 provided by a clutch 40hereinafter more fully described. On the cross feed shaft 34 is a feedpinion 41 in constant mesh with a rack bar 42 on the spindle sleeve 17.

It will be apparent that when the worm and worm wheel 27, 28 of the feedmechanism are in mesh the drum 32 will,be rotated to operate the cam 35,and the latter, through the medium of the cam follower or roller 36 andthe gear segment 37 meshing with the pinion 39, will rotate the crossfeed shaft 34 and thereby the feed pinion 41 to effect the downwardfeeding stroke of the spindle. The feed mechanism may be renderedoperative or inoperative manually in any suitable way,'as for example bymeans of the usual hand lever 43 operatively associated with the movablefeed box 26 so as to move thc the Worm 27 into and out of mesh with theworm wheel 28, the usual disenga eable latch device 44 being provided tohol the worm and worm wheel in mesh.

The cam 35 may be varied at will to 1mpart movements to the tool splndleat the desired speed or speeds. The cam shown herein has three lobeseach of which is shaped to effect initially a rapid approaching movementof the tool spindle followed by a graduall decreasing rate of feed untilthe end of t e downward stroke when the cam is cut away sharply topermit the rapid return of thelspindle under the action of the spring23. With the employment of three lobes on the cam, it will beunderstood, three complete reciprocations of the spindle are effectedduring each complete revolution of the cam.

The clutch connection between the cross feed shaft 34 and the pinion 39is provided in order to permit of adjustments to vary the position ofthe cutting tool at the end of the feeding stroke relative to the work,thus controlling the depth of feed. This clutch connection (Fig. 7)comprises a clutch member 45 with which is rigid the pinion 39 meshingwith the segment 37. This clutch member has inclined clutch teethintermeshing with similar teeth on a second lclutch member 46 rigidlyconnected with the cross feed shaft 34. Connection between the clutchmember 46 and the shaft 34 is accomplished by making the member in twosections 47 and '48 held in position on the shaft by means of a collar49 threaded on the shaft and having a set screw 50. The section 48 ofthe member 46 is keyed on the shaft and is cut away on one side to forma radial rib 51. Engaging with opposite sides of this rib are a pair ofadjusting screws 52 (Fig. 8 mounted in the section 47 which is cup-saped in form, the screws being approximately tangential relativethereto.

This construction normally effects a rigid connection between the twosections of the clutch member 46 and the shaft 34, but one which isadjustable to effect minute variations in the connections of the toolspindle and the actuating cam, su plementing the coarser adjustmentprovi ed between the clutch members themselves as will be more readilyunderstood from the following description of the adjusting operation.

When it is desired to obtain a relatively large adjustment of thespindle with respect to the cam, the collar 49 is first loosened andmoved away from the clutch member 48 a suiiicient distance to permit thedisengagement of the clutch teeth between the members 45 and 46 thusfreeing the cross feed shaft '34 from the cam actuated pinion 39. Theshaft may then be rotated by hand as through the medium of a handle 53so as to adjust the tool dspindle relative to the gear segment 37 andhence to the cam 35. The

adjustment thusprovided is obviously limited to the distance between twoof the teeth of the interengaging clutch members. To effect afineradjustment the two sections of/the clutch member 46 are adjustedrelative to each other by means of the screws 52, it being rememberedthat one of these clutch members is in ldriving relation with the clutchmember carrying the cam driven pinion 39 and the other in drivingrelation to the cross lfeed shaft 34.

' In the present embodiment. it is contemplated that after the feedmechanism has been engaged, by the manual operation of the control lever43,the machine will continue to operate with the spindle making rapidreciprocations to carry the tool toward and from the work. It thereforeis necessary that the successive pieces of work to be operated upon bepresented in timed relation to the reciprocations of the spindle, andthis is accomplished by the automatically operating control mechanism 14operatively connected on the one hand with the cam feed mechanismthrough the medium of the segment 37 (Fig.

2) and connected on the other hand with the rotary work table (Fig. 6).The A.operation ofthe work :table and the control mechanism thereforwill now be described.`

Referring' first to the table as shown in Figs. 1 'and 6, this may be ofany suitable or preferred character.Y Herein it is shown as mounted upona rsupport 54 carried' by a column 55 which also carries the standard10. Onthe support 54 is a'hollow base member 56 which carries the rotarytable 57, the

,intermittent gearing'of the GrenevJ stop type. Herein I have shown suchan indexing mechanism including teeth 58 Withgwhich a roller 59 and anotched disk 60 coact to impart a ste -by-stepl movement to the tablewith a loc ing thereof in operative position during each cuttingoperation. The disk and roller are mounted on a suitable driveractuated:

through the medium of intermeshing worm gears 61 and bevel gears 61a oneof thelatterbeing connected with the source of power.

Referring to Fig. 3, power for driving the machine is applied inysuitable/way to a drive shaft 62 carrying Ain the present instance `apulley wheel' 63. The shaft 62 is supplies power for operating the tablethrough the medium of the control mechanism 14.

Generally stated the control mechanism 14 lcomprises a driving elementconstantly actu ated from the shaft 62, a driven element op- .erativelyconnected With'the table indexing mechanism, and means operatingperiodically inthe movements of the spindle to establish a connectionbetween the driving and I'driven elements whereby a predetermined arc ofmovement will be imparted to the latter once for each reciprocation ofthe spindle. In the present instance, thearrangement is such that at theend of the upward stroke of the spindle and before it commences the nextdownward stroke the table is indexed to remove one `piece of work fromosition beneath the cutting tool andlplace t e next piece of work intooperative position.

As shown in Figs. 2 to 5, 66 designates the constantly 'rotating drivingelement of the control vmechanism, and 67 indicates the driven element.The driving element 66 is in the form of a drum having inclined clutchteeth 68 and arranged to befconnected by a spur gear 69 with a spurpinion 70, the latter being fast on the shaft 62. fThe driven element 67isin the form of a cylinder having a stud shaft 71 rigid therewith andextending into the` driving element 66-, the latter being axially boredfor this purpose. The cylinder 67 is also rigid with a shaft 72extending through'land to one side of the box 13 for connection bysuitable spiral gearing 73, 74 with a shaft 75. The latter may beconnected with the table indexing mechanism by means of a short shaft.section 76 flexibly connected at'opposite ends with the shaft 75 and ashaft 7,7 respectively, the latter carrying one of the bevel gears 61".

To provide for the periodically dis-engage- *able connection between thetwo elements 66 and 67, I employ a pivoted dog 78 (Fig. 5) urged by aspring 79 in the direction o the teeth '68' on the element 66.- Said dogis' mounted in a slot 80 inthe element 67 and projects radially from oneside of the element as shown clearly in Fig. 5. When, therefore,` thedog engageswith the teeth 68, the element 67 is in driven relation tothe element 66 and it will be apparent that upon the disengagement ofthe dog from the teeth 68 the driving relation will be interrupted.

.To provide for the periodic"disengagement of the dog I employ two pinsor studs 81 and 82 mounted-upon diametrically opposite sides of the'element 67 in the path of rotation of the. dog 78. Herein thesejpins81,l

82 are slidable in a stationary yoke member 83 and the pins in turn arerespectively made rigid with arms'Y 84 and 85 mounted upon a rod- 86which -isl slidable in spaced `lbearings 87 formed integral with theyoke member 83. The rod 86 is reciprocable in the bearings 87 and itwill be apparent that the pins 81 and 82 are thereby adapted to be movedsimultaneously so that when one of the pins is moved out of the path ofrotation of the dog lthe other pin is moved into such path.

As shown in Fig. 3, the ends of the pins 81 and 82 adjacent the cylinder67 are beveled and the free end of the dog 78 is oppositely beveled, thearrangement being such that when either of the pins 81, 82 is disposedin the path of rotation ofthe dog the latter striking this pin is cammedoutwardly with respect to the toothed drum 66, so as to disengage thetwo elements 66, 67 from each other. When, therefore, the rod 86 isoperated to move one of the pins, for example, the pin 81 out ofengagement with the dog 78, the latter will under the action of itsspring 79 engage with the toothed drum 66 and rotate therewith carryingthe driven element 67 with it'for approximately one-half revolution oruntil the dog engages the other pin 82 which has been moved intooperative position in the disengagement of the pin 81. Upon theengagement of the dog with the pin 82, the dog becomes disengaged fromthe` toothed drum 66 and the driven element 67 remains stationary untilthe next operation of the rod 86 in the opposite direction. whicheffects another half revolution of the driven element 67 to the positionshown in Figs. 3 and 4.

The means for operating the rod 86 is, as above indicated, controlled bythe movements of the spindle so that at both the upper and lower limitsof the spindle travel the driven element 67 of the control mechanism isreleased for rotation through a half revolution to operate the indexingmechanism. Thev means provided for this purpose comprises in the presentinstance a connection between the control rod 86 and the segment 37,which it will be remembered is geared to the cross feed shaft 34 so asto oscillate in the recip-L rocation of the spindle. This connectioncomprises a link 87 pivotally connected at one end to the rod 86 and atits other end to an arm 88 rigid with the Segment 37. Preferably thelink 87 has interposed therein a rearwardly to disengage the pin 82 fromthe dog 78, whereupon the driven element 67 of the control mechanismoperates through its connections with the indexing mechanism to move theroller 59 through a half revolution. At approximately the same time thefollower-36 rides off from the cam lobe and the spindle under the actionof its spring 23 moves rapidly to its uppermost position. At the end ofthe upward stroke of the spindle the segment 87 moves to its lowermostposition as permitted by the sharp falling off of the cam, and when thesegment reaches this position the rod 86 is again operated, but in theopposite direction, to remove the pin 81 from the path of the dog 78.Accordingl the indexing mechanism is again operate this time to advancethe table one step and lock it in proper position. The spindle nowstarts down with a rapid approach movement under the action of the steepface of the cam, as in the preceding operation.

I claim as m invention:

An automatlc machine tool comprising, in combination, a rotary worktable, a spindle mounted for reciprocation toward and from the table, aspring tending to restrain movement of the spindle in a downwarddirection,

feed mechanism for moving the spindle f downwardly against the action ofsaid spring including a continuously driven cam, a feed shaft geared tothe spindle, a follower for said cam geared to said shaft, an indexingmechanism for the table having a rotatable actuating element,clutch-controlled means for rot-ating said actuating element, and meansoperating as an incident to the movements of the spindle to `controlsaid clutch means and thereby eilect the rotation of said actuatingelement through approximately one-half revolution at each end of thespindle stroke, said actuating element having an operative connectionwith the table effective to advance the table only in the movement ofthe spindle. by said spring.

In testimony'whereof, I have hereunto afiixed my signature.

ALBERT 4M. JOHNSON.

yieldable lost motion connection to avoid the necessity of a delicateadjustment of the parts. This device comprises two telescoplng members89 and 90 having a pin and slot connection 91 and a coiled spring 92which normally acts to hold the members 89 and 90 in extended relation.

Assuming the parts to be in the condition shown in Figs. 2 and 6 withthe spindle in its uppermost position and the table locked: The cam 35operating through the follower 36 swings the segment 37 upwardly firstrapidly to effect the rapid approach of the cutting tool to the work andthen 'more slowly for the feeding cut. At the end of the downwardstroke, with the segment approaching its uppermost position, the rod 87is moved

